WMH Pumper carbs

[86vintage]

I bought a package deal and recieved a set of Pumper Carbs

the top carb has # 3-1B 0670

The middle carb # 7-2 1860

The bottom carb # 7-3 1860

1) do I have a compatable set of carbs?

2) I have seen were people do not use the excelerator pumps - why

3) These carbs are best for what ?

I have two 2.5 litre motors coming together one with full port work and 7 Peddle front half, fiber reeds and reworked cages, high compression, one peice exhaust plate, oval tuner, pinned forged pistons, rods

And another with mildly cleaned ports and no port changes just cleaned up threw the chest and exhaust plate and 2.4 tuner. standard 4 peedle 2.5 reed blocks and fiber reeds and intake 1" spacer

I was hoping some one could let me know the Good and the Bad with these carbs??
I have another set of stantard carbs too.
I am trying to save my money for a SVS or comprible horn but money is tight and thought I would try to build two(2) clean carb engine for next season.
Thanks

James
86vintage

[capnzee]

I am certain that you will hear from a lot of people on this one,but I will pass my experience on to you. To my knowledge mercury built pumpers only one year, around 1993. Your carbs should be numbered 1,2,3 to be matched. The next year they used the same castings but did not use the "pumper" feature. (135's) I built a 2.0 up for the Parker race and had a set of the pumpers. I was warned that they were absolutely no good and to throw them away. I purchased several sets of carburetors in an attempt to get a "good' set. When I received these carbs the venturi's had been reworked making them iillegal. Our class required a 1 5/16" venturi to be legal. I tested with the pumpers (WMH) and they worked great while testing so I decided they would be just fine for the race. The first straight a way was just fine, but once I got into the really rough water the carbs took a dump just as I was told they would. Engine wanted to "flood-out", fuel all over the outside of the engine etc. I found if I held the rrrr's down to around 6300 I could keep it running but when I stood on it and the water got rough the engine would just start to unwind until it quit. With the boat dead in the water and a minute on the starter, I could get it running again until I hit rough water, then all I got was a repeat. Just my experience, I should have listened to the experts--will next time. I have another matched set of the "reworked" carbs, venturis too big for my use, never tried them, wouldn't guarantee a thing. I paid 150 bucks for the three-if you are interested I will sell them for the same plus shipping. Rod

[LightNBug]

The first SST120's had these pieces of junk on them. Merc told everybody they were tested and fine. Also said that was the carb of the future and would be the only ones available. About half way through the first season they sold replacement kits with WH 46's to all the 120 owners at $500 a pop. So I put another $1500 down the tubes to correct Merc's mistake.

[86vintage]

It's to bad the Pumper Carbs look very adjustable with many high tech features. So it sounds like theres an issue with the floats.
Has any one found a solution for these Or as you said JUNK EM!
I run on the ocean so my engines take a beating!

James
86vintage

[LightNBug]

Problem is not floats. Originally it was thought that fuel was sloshing into the vent holes. Not it. Then it was a kit to be installed that disabled the pump circuit. That definantly helped but the pumpers still would not compete with the WH series. Always bogged off the turn. If you jetted enough to stop the bog then the top rpm was down. They had a bigger venturi and were faster top end than the WH's under ideal conditions. Only problem was races were not run in ideal conditions.

[86vintage]

[T-REX]

They don't do worth a crap in drag applications either!!!....Altho, A catfish fisherman could make good use of them...they are juss heavy enuff to hold down a trot line in a stiff current!!!!....

[fyremanbil]

I have an SST120 set also. Will they run well on a ski type 2L boat if the water isnt too bad? Can the adjustments on them be a benefit if your trying to reduce fuel consuption?

[AlanButts]

I have a set of them also, I think they came from smillin jacks , I took a band saw , die grinder , and some epoxy ,to one of them but never finished the project or even started on the other two carbs , but i would'nt write the off as junk yet remember "its what you learn after you know it all that counts"

[T-REX]

"its what you learn after you know it all that counts"

U R so rite.....I made mine work juss great for me.....I took them to tha bandsaw, then throw'd them on tha mill fer a lil mo feness'in, and used the throttle plates for my 10pack project!!....Bout tha only thang I ever could figger pumper carbs wuz good fer!!!....Cept fer trot line sinkerz